Small enhancement to --pages argument parsing

ChangeLog

@@ -1,3 +1,8 @@
+2020-11-09  Jay Berkenbilt  <ejb@ql.org>
+
+	* Handle "." appearing in --pages not preceded by a numeric range
+	as a special case in comand-line parsing code.
+
 2020-11-04  Jay Berkenbilt  <ejb@ql.org>
 
 	* Ignore the value of the offset/generation field in an xref entry

qpdf/qpdf.cc

@@ -2877,9 +2877,17 @@ ArgParser::parsePagesOptions()
                 // The range is invalid.  Let's see if it's a file.
                 try
                 {
-                    fclose(QUtil::safe_fopen(range, "rb"));
-                    // Yup, it's a file.
-                    QTC::TC("qpdf", "qpdf pages range omitted in middle");
+                    if (strcmp(range, ".") == 0)
+                    {
+                        // "." means the input file.
+                        QTC::TC("qpdf", "qpdf pages range omitted with .");
+                    }
+                    else
+                    {
+                        fclose(QUtil::safe_fopen(range, "rb"));
+                        QTC::TC("qpdf", "qpdf pages range omitted in middle");
+                        // Yup, it's a file.
+                    }
                     range_omitted = true;
                 }
                 catch (std::runtime_error&)

qpdf/qpdf.testcov

@@ -456,3 +456,4 @@ qpdf found shared xobject in leaf 0
 QPDF copy foreign with data 1
 QPDF copy foreign with foreign_stream 1
 QPDFObjectHandle need_newline 1
+qpdf pages range omitted with . 0

qpdf/qtest/qpdf.test

@@ -2093,7 +2093,7 @@ foreach my $f (qw(page_api_2 direct-pages))
 show_ntests();
 # ----------
 $td->notify("--- Merging and Splitting ---");
-$n_tests += 26;
+$n_tests += 28;
 
 # Select pages from the same file multiple times including selecting
 # twice from an encrypted file and specifying the password only the
@@ -2149,6 +2149,14 @@ $td->runtest("merge with implicit ranges",
 $td->runtest("check output",
              {$td->FILE => "a.pdf"},
              {$td->FILE => "merge-implicit-ranges.pdf"});
+$td->runtest("merge with . and implicit ranges",
+             {$td->COMMAND =>
+                  "qpdf minimal.pdf a.pdf --pages minimal.pdf . 1 --" .
+                  " --static-id"},
+             {$td->STRING => "", $td->EXIT_STATUS => 0});
+$td->runtest("check output",
+             {$td->FILE => "a.pdf"},
+             {$td->FILE => "merge-dot-implicit-ranges.pdf"});
 $td->runtest("merge with multiple labels",
              {$td->COMMAND =>
                   "qpdf --empty a.pdf" .